# Begin -- grammar generated by Yapps
import sys, re
#import yappsrt
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######################################################################
######################################################################
######################################################################
# The following is the Yapps 2.2.1 runtime file (yappsrt.py)
#
# Yapps 2 Runtime, part of Yapps 2 - yet another python parser system
# Copyright 1999-2003 by Amit J. Patel <amitp@cs.stanford.edu>
#
# This version of the Yapps 2 Runtime can be distributed under the
# terms of the MIT open source license, either found in the LICENSE file
# included with the Yapps distribution
# <http://theory.stanford.edu/~amitp/yapps/> or at
# <http://www.opensource.org/licenses/mit-license.php>
#
"""Run time libraries needed to run parsers generated by Yapps.
This module defines parse-time exception classes, a scanner class, a
base class for parsers produced by Yapps, and a context class that
keeps track of the parse stack.
"""
import sys, re
class SyntaxError(Exception):
"""When we run into an unexpected token, this is the exception to use"""
def __init__(self, charpos=-1, msg="Bad Token", context=None):
Exception.__init__(self)
self.charpos = charpos
self.msg = msg
self.context = context
def __str__(self):
if self.charpos < 0: return 'SyntaxError'
else: return 'SyntaxError@char%s(%s)' % (repr(self.charpos), self.msg)
class NoMoreTokens(Exception):
"""Another exception object, for when we run out of tokens"""
pass
class Scanner:
"""Yapps scanner.
The Yapps scanner can work in context sensitive or context
insensitive modes. The token(i) method is used to retrieve the
i-th token. It takes a restrict set that limits the set of tokens
it is allowed to return. In context sensitive mode, this restrict
set guides the scanner. In context insensitive mode, there is no
restriction (the set is always the full set of tokens).
"""
def __init__(self, patterns, ignore, input):
"""Initialize the scanner.
Parameters:
patterns : [(terminal, uncompiled regex), ...] or None
ignore : [terminal,...]
input : string
If patterns is None, we assume that the subclass has
defined self.patterns : [(terminal, compiled regex), ...].
Note that the patterns parameter expects uncompiled regexes,
whereas the self.patterns field expects compiled regexes.
"""
self.tokens = [] # [(begin char pos, end char pos, token name, matched text), ...]
self.restrictions = []
self.input = input
self.pos = 0
self.ignore = ignore
self.first_line_number = 1
if patterns is not None:
# Compile the regex strings into regex objects
self.patterns = []
for terminal, regex in patterns:
self.patterns.append( (terminal, re.compile(regex)) )
def get_token_pos(self):
"""Get the current token position in the input text."""
return len(self.tokens)
def get_char_pos(self):
"""Get the current char position in the input text."""
return self.pos
def get_prev_char_pos(self, i=None):
"""Get the previous position (one token back) in the input text."""
if self.pos == 0: return 0
if i is None: i = -1
return self.tokens[i][0]
def get_line_number(self):
"""Get the line number of the current position in the input text."""
# TODO: make this work at any token/char position
return self.first_line_number + self.get_input_scanned().count('\n')
def get_column_number(self):
"""Get the column number of the current position in the input text."""
s = self.get_input_scanned()
i = s.rfind('\n') # may be -1, but that's okay in this case
return len(s) - (i+1)
def get_input_scanned(self):
"""Get the portion of the input that has been tokenized."""
return self.input[:self.pos]
def get_input_unscanned(self):
"""Get the portion of the input that has not yet been tokenized."""
return self.input[self.pos:]
def token(self, i, restrict=None):
"""Get the i'th token in the input.
If i is one past the end, then scan for another token.
Args:
restrict : [token, ...] or None; if restrict is None, then any
token is allowed. You may call token(i) more than once.
However, the restrict set may never be larger than what was
passed in on the first call to token(i).
"""
if i == len(self.tokens):
self.scan(restrict)
if i < len(self.tokens):
# Make sure the restriction is more restricted. This
# invariant is needed to avoid ruining tokenization at
# position i+1 and higher.
if restrict and self.restrictions[i]:
for r in restrict:
if r not in self.restrictions[i]:
raise NotImplementedError("Unimplemented: restriction set changed")
return self.tokens[i]
raise NoMoreTokens()
def __repr__(self):
"""Print the last 10 tokens that have been scanned in"""
output = ''
for t in self.tokens[-10:]:
output = '%s\n (@%s) %s = %s' % (output,t[0],t[2],repr(t[3]))
return output
def scan(self, restrict):
"""Should scan another token and add it to the list, self.tokens,
and add the restriction to self.restrictions"""
# Keep looking for a token, ignoring any in self.ignore
while 1:
# Search the patterns for the longest match, with earlier
# tokens in the list having preference
best_match = -1
best_pat = '(error)'
for p, regexp in self.patterns:
# First check to see if we're ignoring this token
if restrict and p not in restrict and p not in self.ignore:
continue
m = regexp.match(self.input, self.pos)
if m and len(m.group(0)) > best_match:
# We got a match that's better than the previous one
best_pat = p
best_match = len(m.group(0))
# If we didn't find anything, raise an error
if best_pat == '(error)' and best_match < 0:
msg = 'Bad Token'
if restrict:
msg = 'Trying to find one of '+', '.join(restrict)
raise SyntaxError(self.pos, msg)
# If we found something that isn't to be ignored, return it
if best_pat not in self.ignore:
# Create a token with this data
token = (self.pos, self.pos+best_match, best_pat,
self.input[self.pos:self.pos+best_match])
self.pos = self.pos + best_match
# Only add this token if it's not in the list
# (to prevent looping)
if not self.tokens or token != self.tokens[-1]:
self.tokens.append(token)
self.restrictions.append(restrict)
return
else:
# This token should be ignored ..
self.pos = self.pos + best_match
class Parser:
"""Base class for Yapps-generated parsers.
"""
def __init__(self, scanner):
self._scanner = scanner
self._pos = 0
def _peek(self, *types):
"""Returns the token type for lookahead; if there are any args
then the list of args is the set of token types to allow"""
tok = self._scanner.token(self._pos, types)
return tok[2]
def _scan(self, type):
"""Returns the matched text, and moves to the next token"""
tok = self._scanner.token(self._pos, [type])
if tok[2] != type:
raise SyntaxError(tok[0], 'Trying to find '+type+' :'+ ' ,'.join(self._scanner.restrictions[self._pos]))
self._pos = 1 + self._pos
return tok[3]
class Context:
"""Class to represent the parser's call stack.
Every rule creates a Context that links to its parent rule. The
contexts can be used for debugging.
"""
def __init__(self, parent, scanner, tokenpos, rule, args=()):
"""Create a new context.
Args:
parent: Context object or None
scanner: Scanner object
pos: integer (scanner token position)
rule: string (name of the rule)
args: tuple listing parameters to the rule
"""
self.parent = parent
self.scanner = scanner
self.tokenpos = tokenpos
self.rule = rule
self.args = args
def __str__(self):
output = ''
if self.parent: output = str(self.parent) + ' > '
output += self.rule
return output
def print_line_with_pointer(text, p):
"""Print the line of 'text' that includes position 'p',
along with a second line with a single caret (^) at position p"""
# Now try printing part of the line
text = text[max(p-80, 0):p+80]
p = p - max(p-80, 0)
# Strip to the left
i = text[:p].rfind('\n')
j = text[:p].rfind('\r')
if i < 0 or (0 <= j < i): i = j
if 0 <= i < p:
p = p - i - 1
text = text[i+1:]
# Strip to the right
i = text.find('\n', p)
j = text.find('\r', p)
if i < 0 or (0 <= j < i): i = j
if i >= 0:
text = text[:i]
# Now shorten the text
while len(text) > 70 and p > 60:
# Cut off 10 chars
text = "..." + text[10:]
p = p - 7
# Now print the string, along with an indicator
print >>sys.stderr, '> ',text
print >>sys.stderr, '> ',' '*p + '^'
def print_error(input, err, scanner):
"""Print error messages, the parser stack, and the input text -- for human-readable error messages."""
# NOTE: this function assumes 80 columns :-(
# Figure out the line number
line_number = scanner.get_line_number()
column_number = scanner.get_column_number()
print >>sys.stderr, '%d:%d: %s' % (line_number, column_number, err.msg)
context = err.context
if not context:
print_line_with_pointer(input, err.charpos)
while context:
# TODO: add line number
print >>sys.stderr, 'while parsing %s%s:' % (context.rule, tuple(context.args))
print_line_with_pointer(input, context.scanner.get_prev_char_pos(context.tokenpos))
context = context.parent
def wrap_error_reporter(parser, rule):
try:
return getattr(parser, rule)()
except SyntaxError, e:
input = parser._scanner.input
print_error(input, e, parser._scanner)
except NoMoreTokens:
print >>sys.stderr, 'Could not complete parsing; stopped around here:'
print >>sys.stderr, parser._scanner
######################################################################
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class YappsRT:
pass
yappsrt = YappsRT()
yappsrt.Scanner = Scanner
yappsrt.Parser = Parser
yappsrt.Context = Context
yappsrt.SyntaxError = SyntaxError
yappsrt.NoMoreTokens = NoMoreTokens
yappsrt.wrap_error_reporter = wrap_error_reporter
######################################################################
# The following is generated by Yapps2.1.1:
class _SLParserBaseScanner(yappsrt.Scanner):
patterns = [
('"-"', re.compile('-')),
('"="', re.compile('=')),
('"\\]"', re.compile('\\]')),
('"\\["', re.compile('\\[')),
('","', re.compile(',')),
('";"', re.compile(';')),
('"}"', re.compile('}')),
('"{"', re.compile('{')),
('"\\)"', re.compile('\\)')),
('"\\("', re.compile('\\(')),
('[ \n\t]+', re.compile('[ \n\t]+')),
('END', re.compile('$')),
('number', re.compile('[0-9]+(\\.[0-9]*)?([eE][0-9]+)?|\\.[0-9]+([eE][0-9]+)?')),
('stringconstant', re.compile('"[^"]*"')),
('shader_type', re.compile('(light|surface|volume|displacement|imager)')),
('outputspec', re.compile('output')),
('type', re.compile('(float|string|color|point|vector|normal|matrix|void)')),
('detail', re.compile('(varying|uniform)')),
('singletypes', re.compile('(float|string)')),
('spacetypes', re.compile('(color|point|vector|normal|matrix)')),
('identifier', re.compile('[_a-zA-Z][_a-zA-Z0-9]*')),
('binop', re.compile('[+\\-/^*.]')),
('preprocessorline', re.compile('#.*')),
]
def __init__(self, str):
yappsrt.Scanner.__init__(self,None,['[ \n\t]+'],str)
class _SLParserBase(yappsrt.Parser):
Context = yappsrt.Context
def definitions(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'definitions', [])
shaders = []
while self._peek('END', 'preprocessorline', 'shader_type', 'type', 'identifier') != 'END':
_token = self._peek('preprocessorline', 'shader_type', 'type', 'identifier')
if _token == 'preprocessorline':
preprocessorline = self._scan('preprocessorline')
self.switchFile(preprocessorline)
elif _token == 'shader_type':
shader_def = self.shader_def(_context)
shaders.append(shader_def)
else: # in ['type', 'identifier']
function_def = self.function_def(_context)
if self._peek() not in ['END', 'preprocessorline', 'shader_type', 'type', 'identifier']:
raise yappsrt.SyntaxError(charpos=self._scanner.get_prev_char_pos(), context=_context, msg='Need one of ' + ', '.join(['preprocessorline', 'END', 'shader_type', 'type', 'identifier']))
END = self._scan('END')
return shaders
def shader_def(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'shader_def', [])
shader_type = self._scan('shader_type')
identifier = self._scan('identifier')
self.newParams()
self._scan('"\\("')
if self._peek('"\\)"', 'outputspec', '";"', 'detail', 'type', '","') in ['outputspec', 'detail', 'type']:
formals = self.formals(_context)
self._scan('"\\)"')
self._scan('"{"')
self._scan('"}"')
return (shader_type,identifier,self.params)
def function_def(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'function_def', [])
if self._peek('type', 'identifier') == 'type':
type = self._scan('type')
identifier = self._scan('identifier')
self._scan('"\\("')
if self._peek('"\\)"', 'outputspec', '";"', 'detail', 'type', '","') in ['outputspec', 'detail', 'type']:
formals = self.formals(_context)
self._scan('"\\)"')
self._scan('"{"')
self._scan('"}"')
def formals(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'formals', [])
formal_var_defs = self.formal_var_defs(_context)
while self._peek('";"', '"\\)"', '","') == '";"':
self._scan('";"')
if self._peek('outputspec', '";"', 'detail', 'type', '","', '"\\)"') in ['outputspec', 'detail', 'type']:
formal_var_defs = self.formal_var_defs(_context)
if self._peek() not in ['";"', '"\\)"', '","']:
raise yappsrt.SyntaxError(charpos=self._scanner.get_prev_char_pos(), context=_context, msg='Need one of ' + ', '.join(['";"', '"\\)"', '","']))
def formal_var_defs(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'formal_var_defs', [])
self.newType()
if self._peek('outputspec', 'detail', 'type') == 'outputspec':
outputspec = self._scan('outputspec')
self.output="output"
typespec = self.typespec(_context)
def_expressions = self.def_expressions(_context)
def typespec(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'typespec', [])
if self._peek('detail', 'type') == 'detail':
detail = self._scan('detail')
self.detail = detail
type = self._scan('type')
self.type = type
def def_expressions(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'def_expressions', [])
def_expression = self.def_expression(_context)
while self._peek('","', '";"', '"\\)"') == '","':
self._scan('","')
def_expression = self.def_expression(_context)
if self._peek() not in ['","', '";"', '"\\)"']:
raise yappsrt.SyntaxError(charpos=self._scanner.get_prev_char_pos(), context=_context, msg='Need one of ' + ', '.join(['","', '";"', '"\\)"']))
def def_expression(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'def_expression', [])
identifier = self._scan('identifier')
self.name = identifier
if self._peek('"\\["', '"="', '","', '";"', '"\\)"') == '"\\["':
self._scan('"\\["')
number = self._scan('number')
self._scan('"\\]"')
self.arraylen=int(number)
if self._peek('"="', '","', '";"', '"\\)"') == '"="':
def_init = self.def_init(_context)
self.default = def_init
self.storeParam()
def def_init(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'def_init', [])
self._scan('"="')
expression = self.expression(_context)
return expression
def expression(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'expression', [])
expr=""
_token = self._peek('"-"', 'number', 'stringconstant', 'singletypes', 'spacetypes', '"\\("', '"{"', 'identifier')
if _token not in ['"-"', 'singletypes', 'spacetypes']:
primary = self.primary(_context)
expr+=primary
elif _token == '"-"':
self._scan('"-"')
expression = self.expression(_context)
expr+="-"+expression
else: # in ['singletypes', 'spacetypes']
typecast = self.typecast(_context)
expression = self.expression(_context)
expr+=expression
while self._peek('binop', '","', '"\\)"', '"}"', '";"') == 'binop':
binop = self._scan('binop')
expression = self.expression(_context)
expr+=binop+expression
if self._peek() not in ['binop', '","', '"\\)"', '"}"', '";"']:
raise yappsrt.SyntaxError(charpos=self._scanner.get_prev_char_pos(), context=_context, msg='Need one of ' + ', '.join(['binop', '","', '"\\)"', '"}"', '";"']))
return expr
def primary(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'primary', [])
_token = self._peek('number', 'stringconstant', '"\\("', '"{"', 'identifier')
if _token == 'number':
number = self._scan('number')
return number
elif _token == 'stringconstant':
stringconstant = self._scan('stringconstant')
return stringconstant
elif _token == '"\\("':
tuple = self.tuple(_context)
return tuple
elif _token == '"{"':
array = self.array(_context)
return array
else: # == 'identifier'
identifier_or_procedurecall = self.identifier_or_procedurecall(_context)
return identifier_or_procedurecall
def tuple(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'tuple', [])
tup = ""
self._scan('"\\("')
expression = self.expression(_context)
tup+=expression
while self._peek('"\\)"', '","') == '","':
self._scan('","')
expression = self.expression(_context)
tup+=", "+expression
if self._peek() not in ['"\\)"', '","']:
raise yappsrt.SyntaxError(charpos=self._scanner.get_prev_char_pos(), context=_context, msg='Need one of ' + ', '.join(['","', '"\\)"']))
self._scan('"\\)"')
return "("+tup+")"
def typecast(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'typecast', [])
_token = self._peek('singletypes', 'spacetypes')
if _token == 'singletypes':
singletypes = self._scan('singletypes')
else: # == 'spacetypes'
spacetypes = self._scan('spacetypes')
if self._peek('stringconstant', '"-"', 'number', 'singletypes', 'spacetypes', '"\\("', '"{"', 'identifier') == 'stringconstant':
spacename = self.spacename(_context)
self.space = spacename[1:-1]
def spacename(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'spacename', [])
stringconstant = self._scan('stringconstant')
return stringconstant
def identifier_or_procedurecall(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'identifier_or_procedurecall', [])
identifier = self._scan('identifier')
res = identifier; proc_args=""
if self._peek('"\\("', 'binop', '","', '"\\)"', '"}"', '";"') == '"\\("':
self._scan('"\\("')
if self._peek('"\\)"', '"-"', 'number', 'stringconstant', 'singletypes', 'spacetypes', '"\\("', '"{"', 'identifier') != '"\\)"':
proc_args = self.proc_args(_context)
self._scan('"\\)"')
res+="("+proc_args+")"
return res
def proc_args(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'proc_args', [])
expression = self.expression(_context)
res = expression
while self._peek('","', '"\\)"') == '","':
self._scan('","')
expression = self.expression(_context)
res+=", "+expression
if self._peek() not in ['","', '"\\)"']:
raise yappsrt.SyntaxError(charpos=self._scanner.get_prev_char_pos(), context=_context, msg='Need one of ' + ', '.join(['","', '"\\)"']))
return res
def array(self, _parent=None):
_context = self.Context(_parent, self._scanner, self._pos, 'array', [])
arr = ""
self._scan('"{"')
expression = self.expression(_context)
arr+=expression; self.appendSpace()
while self._peek('"}"', '","') == '","':
self._scan('","')
expression = self.expression(_context)
arr+=", "+expression; self.appendSpace()
if self._peek() not in ['"}"', '","']:
raise yappsrt.SyntaxError(charpos=self._scanner.get_prev_char_pos(), context=_context, msg='Need one of ' + ', '.join(['","', '"}"']))
self._scan('"}"')
return "{"+arr+"}"
def parse(rule, text):
P = _SLParserBase(_SLParserBaseScanner(text))
return yappsrt.wrap_error_reporter(P, rule)
if __name__ == '__main__':
from sys import argv,stdin
if len(argv) >= 2:
if len(argv) >= 3:
f = open(argv[2],'r')
else:
f = stdin
print parse(argv[1], f.read())
else: print >>sys.stderr, 'Args: <rule> [<filename>]'
# End -- grammar generated by Yapps
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